Plasma levels of DDE/DDT and liver function in malaria control personnel 6 months after indoor residual spraying with DDT in northern Uganda, 2008

Abstract

Objective. We investigated the relationship between plasma levels of dichlorodiphenyltrichloroethane (DDT) and liver function in malaria control personnel 6 months after one round of DDT indoor residual spraying (IRS). Method. This was a cross-sectional study in the districts of Apac and Oyam of Lango, northern Uganda. Volunteers were clinically examined, and 5 ml samples of venous blood were taken in heparinised tubes for a 6-month post-spray screening for DDT and plasma markers of liver function and internal organ disease. DDE/DDT was assayed using ELISA kits (Abraxis, USA); plasma enzyme activity concentrations of amylase, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and gamma glutamyl transpeptidase (GGT) were analysed using routine clinical chemistry automated methods (Konelab, Vantaa, Finland). Results. All 96 plasma samples analysed for xenobiotics contained DDE/DDT in the empirical range of 24.00 - 128.00 parts per billion (ppb) with a mean (SD) of 77.00 (±26.00) ppb. All 119 plasma samples studied for the markers exhibited enzyme activity concentration values within the population reference ranges, with empirical means (SD) of amylase 71.86 (34.07), AST 23.83 (12.71), ALT 7.84 (10.01) and GGT 58.37 (62.68) µg/l. Conclusion. Six months after IRS with DDT, the spray team had an average concentration of plasma DDE/DDT of 77 ppb. This had no deleterious effect on liver function. We recommend continued use of DDT for IRS disease control in Uganda until better practical alternatives are available.